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Traditional cyclic prefix-orthogonal frequency division multiplexing is a popular multicarrier modulation (MCM) scheme, which provides advantages of good bandwidth utilisation and simplicity in transceiver design. However, the waveform suffers from poor spectral utilisation due to the utilisation of rectangular window and lack of flexibility. Hence, an alternative MCM scheme based on wavelet filter-bank architecture is considered in this study for fifth-generation wireless access systems. Cyclostationarity-based joint sensing and channel equalisation is applied at the receiver side, which demonstrates improved signal detection performance. Adaptive line enhancement adaptive line enhancement (ALE)-based noise cancellation is explored to improve the sensing performance. The combined noise cancellation and sensing scheme improve the cyclostationarity-based equalisation and demodulation performance. [ABSTRACT FROM AUTHOR]

This study aims to implement the telematics between hybrid rockets and the ground receiving station. In order to significantly reduce the rocket weight, fibre-reinforced plastic is used for the hybrid rocket casing, on which coplanar wraparound antennas with an operating frequency of 433 MHz are designed. The antenna structure contains three coplanar printed patches, among which the middle printed patch is the primary radiator and the resonant length appears a wavelength for the metallic surface case. An RF module with high receiver sensitivity and a high-power power amplifier are included to enhance the communication coverage of hybrid rockets and the ground receiving station so that the station can effectively track the hybrid rocket. Finally, the radio wave propagation model is used for calculating the link budget such that the communication coverage between rocket transmitters and the ground receiving station can be estimated, and on-site measurement and verification are preceded. [ABSTRACT FROM AUTHOR]

This paper presents some preliminary results from experimental studies on space-division-multiple-access (SDMA) for wireless communications. A smart antenna system utilizing direction-of-arrival (DOA)-based beamforming techniques can enhance signal quality by reducing co-channel interference from mobiles located at angles spatially distinct from the base station. Adopting both smart uplink and downlink beamforming, a communication system with an antenna array can increase the cell coverage of a base station and significantly boost capacity compared with conventional antenna systems. However, successful implementation of DOA-based beamforming techniques depends on the DOA characteristics. This paper presented the feasibility of direction finding and DOA variation with respect to frequency. Furthermore, the angle spread was studied for selected environments. The results demonstrate the feasibility of applying proposed smart antenna system utilizing DOA-based beamforming algorithm for increasing channel capacity and improving system performance in frequency-division-duplex (FDD) wireless communication systems. Copyright © 2003 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]